/****************************************************************************** $Id: qt/main.cpp   3.3.4   edited Sep 10 2003 $**** Copyright (C) 1992-2002 Trolltech AS.  All rights reserved.**** This file is part of an example program for Qt.  This example** program may be used, distributed and modified without limitation.*******************************************************************************/#include "main.h"#include <qdatatable.h>InvoiceItemCursor::InvoiceItemCursor() :    QSqlCursor( "invoiceitem" ){    QSqlFieldInfo productName( "productname", QVariant::String );    append( productName );    setCalculated( productName.name(), TRUE );    QSqlFieldInfo productPrice( "price", QVariant::Double );    append( productPrice );    setCalculated( productPrice.name(), TRUE );    QSqlFieldInfo productCost( "cost", QVariant::Double );    append( productCost );    setCalculated( productCost.name(), TRUE );}QVariant InvoiceItemCursor::calculateField( const QString & name ){    if ( name == "productname" ) {	QSqlQuery query( "SELECT name FROM prices WHERE id=" +		     field( "pricesid" )->value().toString() );	if ( query.next() )	    return query.value( 0 );    }    else if ( name == "price" ) {	QSqlQuery query( "SELECT price FROM prices WHERE id=" +		     field( "pricesid" )->value().toString() );	if ( query.next() )	    return query.value( 0 );    }    else if ( name == "cost" ) {	QSqlQuery query( "SELECT price FROM prices WHERE id=" +		     field( "pricesid" )->value().toString() );	if ( query.next() )	    return QVariant( query.value( 0 ).toDouble() *			     value( "quantity").toDouble() );    }    return QVariant( QString::null );}QSqlRecord *InvoiceItemCursor::primeInsert(){    QSqlRecord *buffer = editBuffer();    QSqlQuery query( "SELECT NEXTVAL( 'invoiceitem_seq' )" );    if ( query.next() )	buffer->setValue( "id", query.value( 0 ) );    buffer->setValue( "paiddate", QDate::currentDate() );    buffer->setValue( "quantity", 1 );    return buffer;}int main( int argc, char *argv[] ){    QApplication app( argc, argv );    if ( createConnections() ) {	InvoiceItemCursor invoiceItemCursor;	QDataTable *invoiceItemTable = new QDataTable( &invoiceItemCursor );	app.setMainWidget( invoiceItemTable );	invoiceItemTable->addColumn( "productname", "Product" );	invoiceItemTable->addColumn( "price",	    "Price" );	invoiceItemTable->addColumn( "quantity",    "Quantity" );	invoiceItemTable->addColumn( "cost",	    "Cost" );	invoiceItemTable->addColumn( "paiddate",    "Paid" );	invoiceItemTable->refresh();	invoiceItemTable->show();	return app.exec();    }    return 1;}